He's Led Zeppelin's famous voice, she's known as one of Nashville's most talented fiddle players and singers. In 2007, Robert Plant and Alison Krauss collaborated to create a powerful duo album, Raising Sand, pleasing critics and fans alike. The album's greatest praise has been for the stellar harmony of Plant and Krauss' vocals. Krauss has helped generate a new interest in bluegrass music in the United States. She garnered much attention from her soundtracks, especially the Grammy Winning "O Brother, Where Art Thou?" and Cold Mountain soundtracks. During her career she has won 21 Grammy Awards, more than any other female artist. Plant's fame as Led Zeppelin's lead vocalist makes him one of the most celebrated singer/songwriters today. His signature scream and passionate voice make him rock's penultimate front man. Today Plant experiments with solo work and duets such as his work with Alison Krauss.